Adjusting means for spring screw-threading dies and hollow mills.



L A. BARTELS.

ADJUSTING MEANS FOR SPRING SCREW THREADING DIES AND HOLLOW MILLS.

APPLICATION FILED NOV. \9. 1912.

v 1,164,67, Patented Dec.14,1915.

' amto'a LUCAS A. BABTELS, 0F HARTFORD, CONNECTICUT.

ADJUSTING MEANS FOR SPRING SCREW-THREADING DIES AND HOLLOW MILLS.

Specification of Letters Patent.

Patented Dec. T4, 1915.

Application filed November 19, 1912. Serial No. 732,304.

To all whom it may concern Be it known that I, LUCAS A. BARTELS, acitizen of the United States, residing at Hartford, in the county ofHartford and State of Connecticut, have invented new and usefulImprovements in Adjusting Means for Spring Screw-Threading Dies andHollow Mills, of which the following is a specification.

The invention relates generally to an improvement in spring screwthreading dies and hollow mills, and particularly to a means foradjusting such parts in a simple and accurate manner.

The main object of the invention resides in the production of a ringarranged for threaded engagement with the threading die or hollow mill,and which through the peculiar formation of the threaded surfaces of thedie or mill and ring, will adjust such die or mill.

The invention will be described in the following specification,reference being had particularly to the accompanying drawing, in which:

Figure 1 is a view in elevation partly in section illustrating theimprovement as applied to a spring screw threading die. Fig. 2 is asectional view of the ring. Fig. 3 is a view similar to Fig. 1 showingthe invention applied to a hollow mill. Fig. 4 is a detail sectionalview illustrating the manner of engagement of the prongs with theadjusting ring.

In the details of improvement the threading die or hollow mill, as thecase may be, is exteriorly threaded at l and such threading is peculiarin that the depth of each succeeding thread from the operative end ofthe die or mill toward the opposite end is of reduced depth, as viewedin section, or in other words the threading channel on the die or millhas its maximum depth at the initial or entrant end, and is graduallyand uniformly reduced in depth therefrom toward the opposite end.

The adjusting ring 2, which is interiorly of a size to cooperate withthe die or mill is interiorly threaded at 3, said threads having a pitchto engage with the threads on the die or mill but the threaded surfaceof the ring is tapered with the larger end of a size to exactlycooperate with the initial thread channel on the die or mill withoutcompression of the parts.

In use the ring is threaded upon the die or mill to accomplish a desiredadjustment it being noted that the gradual reduction in the depth of thethreaded channel of the die or mill together with the taperedarrangement of the threaded portion within the ring insures suchmovement of the prongs or lands as will provide for the desiredadjustment.

The improvement is of material advantage over other adjusting meansheretofore provided in that it insures an absolutely uniform movement ofthe lands in the adjusting operation, so that when adjusted the work ofthe lands will be evenly distributed between all of them and no one willwear more than another. Furthermore the uniform movement of all lands inthe adjustment prevents threading off center and thereby insures moreperfect work. The ring may be readily and conveniently applied and inuse will even tend to correct irregularity in the position of the landsincident to there having to come out of shape during the hardeningprocess. The ring may be formed exteriorly in any way to provide for itsready operation in appl fing it to or removing it from the die or m1Having thus described the invention, what I claim as new, is:

A cutting implement having prongs and formed with an adjusting threadchannel, said channel being of gradually decreasing depth from theentrant end, and a ring arranged for threaded connection with saidchannel, said ring being interiorly threaded throughout a taperedsurface.

In testimony whereof I affix my signature in presence of two witnesses.

LUCAS A. BARTELS.

Witnesses:

WILLIAM F. HUssEY, ALBERT BAUMGARTEN.

Gopies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

